Portlet Development Extension

Allows management of:

• Configuration files 
• Custom source code 
• Custom JSPs 
• Modified JSPs 

Provides different sublevels of extensibility


portal(-ext).properties

• Main configuration options: deployment, themes, hibernate, cache, instance settings, users, groups, language, session, auth, integration, events, ... 

system(-ext).properties
Convenient way to provide and extend the Java System properties used by Liferay

• The extension points or hooks allow creating custom classes for the most common extensibility needs 
• Configurable through portal.properties 
• Examples: Authentication chain, Upgrade and verification processes, Deployment processes, Database access and caching, User fields generation and validation, session events, permissions, model listeners, ext-spring.xml